I. Field of Invention
This invention relates in general to ammunition handling for muzzle loaded mortars and, in particular, to automated assistance for loading ammunition into a mortar through the muzzle.
II. Background of the Invention
Mortars are muzzle loading cannons used to fire shells at short range and high angular elevation. They are loaded by manually dropping a shell down the barrel of the muzzle, and fire immediately when the shell impacts a fixed firing pin located at the bottom of the bore.
Mortars are typically emplaced on the ground in defilade but are also integrated into vehicles. In either case, the loading procedure exposes the soldier to enfilade fire. This invention assists the soldier by transporting the shell into the muzzle from a lower position near the base of the cannon thus reducing such exposure. It further reduces a soldier""s exposure to the effects of the muzzle blast.
Accordingly, it is an object of this invention to provide a power assisted shell loader for mortars which minimizes the operator""s exposure to blast and enemy fire.
Still another object of this invention is to load a shell into the mortar at any angle of elevation that the mortar is expected to fire.
Another object is to provide a device that is compatible with currently fielded mortars.
An additional object is to provide a simple, low cost device having low power consumption.
Finally, another object of the invention is to provide a device having a design that can be easily modified to achieve further automation by the addition of a magazine to store and issue shells to the loader device.
It has now been discovered that the above and other objects of the present invention may be accomplished in the following manner.
Specifically, there is provided a loader assist comprising a frame surrounding the mortar and attached thereto. The said frame being supported on pivots mounted to a turntable such that both the invention and mortar move as one, through azimuth and elevation. A lift device, comprised of a linear actuator to provide motion, a lift bracket, which engages the base of the shell, and guides to provide lateral support, is positioned at the center of the frame and parallel to the mortar axis. A carriage comprising a transfer device is positioned on top of said frame, perpendicular to the mortar axis, and movable on ways, from the axis of said lift, to the axis of the mortar. Said elevator is comprised of two linear actuators, each having a shuttle with two moveable jaws, spring biased downward, and moveable beyond the muzzle of the mortar. Said actuators are positioned opposite each other such that the jaws on each shuttle can act in pairs, with the respective jaws on the other, to grip the shell in two places. Each jaw has a cam follower, biased by a cam mounted to its respective actuator, and moveable to engage or disengage said follower. Said cams are biased to engage said followers when the carriage is positioned at the mortar, and oppositely biased to disengage the followers when the carriage approaches the lift position. A control device sequences the motion of all actuators.
To load and fire the mortar, a shell is placed in the guides of the lift actuator. A firing switch, conveniently placed, is actuated to initiate the action. Said actuator lifts the shell above the frame to hand it off to the transfer assembly, said shell displacing the elevator jaws until they fully engage and capture the shell, whereupon the lift actuator retracts to its starting position. The transfer assembly shuttles then raise the shell beyond the muzzle, translate it to the axis of the mortar, and insert it into the tube. During the downward insertion motion, the cam followers on the jaws engage the cam surfaces, sequently lifting each jaw as it approaches the muzzle thereby providing full support for the shell until it rides freely in the bore of the mortar. As the elevator shuttles reach their end of travel, the carriage moves back to the lift actuator, disengaging the cams and allowing the jaws to drop to their lowered position, whereupon the cycle may be repeated with another shell.